As of June 2024, child marriage, defined as marriage where at least one party is under 18, is still legal in 36 out of 50 U.S. states, which works out to 72%. The claim of "80%" on internet sources is slightly off but close enough to reflect the broader issue.
According to data from Unchained At Last and other sources like Equality Now and Wikipedia (last updated April 2025), 14 states have banned child marriage outright, setting the minimum age at 18 with no exceptions (e.g., parental or judicial consent). These are Delaware (2018), New Jersey (2018), Pennsylvania (2020), Minnesota (2020), Rhode Island (2021), New York (2021), Massachusetts (2022), Vermont (2023), Connecticut (2023), Michigan (2023), Washington (2024), Virginia (2024), New Hampshire (2024), and Missouri (2025). That leaves 36 states where minors can marry, usually with loopholes like parental permission or a judge's approval.
In these 36 states, laws vary. Ten states set a minimum age of 17, 23 have it at 16, two at 15, and five (like California and Mississippi) have no minimum age at all if certain conditions are met (e.g., pregnancy or judicial waiver). For example, Missouri raised its minimum to 16 in 2018 but only banned under-18 marriage in 2025.
Between 2000 and 2018, nearly 300,000 minors were married in the U.S., mostly girls (86%) wed to adult men, some as young as 10. Texas led with 41,774 cases, California had 23,588, and Nevada's lax laws made it a hotspot. The numbers have dropped (2,493 in 2018 vs. 76,396 in 2000), but without bans, it won't hit zero.
Loopholes persist due to cultural, religious, or legal arguments. Conservatives sometimes defend it to avoid "illegitimate" births or uphold traditions, while progressives (e.g., California's ACLU in 2017) argue bans could limit minors' choices in abusive situations. Both sides face criticism for enabling harm, as child marriage is linked to higher poverty (31% more likely), school dropout (50% more likely), and abuse.
https://19thnews.org/2023/07/explaining-child-marriage-laws-united-states/